The RMS voltage (V-RMS) of a sinusoidal waveform is determined by multiplying the peak voltage value by 0.7071, which is the same as one divided by the square root of two ( 1/√2 ).
[tex]V_{RMS}=V_{PK}\times\frac{1}{\sqrt[]{2}}=V_{PK}\times0.7071[/tex]The question provides that:
[tex]V=60\sin \theta[/tex]The peak voltage is at
[tex]\theta=90\degree[/tex]Therefore, the peak voltage is given to be:
[tex]V_{PK}=60\sin (90)=60[/tex]Hence, the RMS voltage is gotten to be:
[tex]V_{\text{RMS}}=60\times0.7071=42.42[/tex]The correct option is OPTION D.
